Stitch-forming means for sewing-machines.



PATENTED APR. 24, 1906.

R. L. LYONS. STITCH FORMING MEANS FOR SEWING MACHINES.

APPLICATION FILED DEC.19,1904.

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PATENTED APR. 24, 1906.

R. L. LYONS. STITCH FORMING MEANS FOR SEWING MACHINES.

3 SHEETSSHEET 2 APPLICATION FILED DEC. 19, 1904.

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R. L. LYONS. STITCH FORMING MEANS FOR SEWING MAGHINES.

APPLICATION FILED 13110.19, 1904.

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TED STATES -No. 818,840. Specification of PATENT LTH A M, M as SA 0 H u FOR SEWIlMlG-It'lfitCl-SINESa Letters Patent. Patented April :34, 1906.

Application filed December 19,1904. Serial No. 237.376.

To all whom it may concern;

Be it known that I, ROBERT L. LYONs, of IValtham, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Stitch- Forming Means for Sewing-Machines; and I1 hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates to improvements in stitch-forming means for sewing-machines, and particularly to-single-thread'sewing-machines for forming a group of stitches.

One object of the invention is to sever the thread beneath the work at the completion of a group of stitches without the use of mechanical severing devices other than the work.

Another object of the invention is to sever the thread beneath the work through the instrumentality .of mechanism located above the work. I

Another object of the invention is to im prove the sewing-machine with reference to the stitch-forming and thread scvcr1ng means The invention consists in means for forming a group ofstitchesand, asso called, knottingthe thread at the completion of said group of stitches, together with means for locking the thread above the work, and other means for taking up the thread between the point at which it is locked and the work.

The invention also consists in such other novel features of construction and combination of parts as shall hereina ftcr be more fully described, and pointed out in the claims.

Figure 1 represents a side elevation of the lmproved sewing-machine, parts of the same being broken away. Fig. 2 represents a plan View of parts of the same. Fig. 3 represents a cross-sectional view taken on line 3 3, Fig. 2. Fig. 4 represents a bottom plan viewof parts of the machine, particularly with reference to the means for moving the workwith respect to the path of the needle and for holding the work, at the completion of a group of stitches, in position to receive two or more loop-delivery actions of the needle. Fig. 5 represents a diagrammatic view of portions of the ma chine and the work at or about the time the chain is formed after the group of stitches has been formed and approximately as the last upward stroke of the needle commences, which effects the taking upofJthe thread to break the same below the work. Fig. 6 represents'an enlarged view of portions of the same as the loops of the knotted portions or the thread are generally arranged at the time :tlIC thread is severed and approximately ind icating the point at which the thread is sevcred.

Similar numbers of reference designate corresponding parts throughout.

In carrying this invention into practice i first form a group of stitches by producing a relative movement between the needle and the work by any well-known means, or by a combination of both of said movements, the number of stitches in said group depending upon the nature of the work, as usual. At about the completion ofthe group of stitches l stop the lateral.movementof thework or the vibration of the needle, so that a series of loops of thread are carried by the needle to the loopcr,preferably without cmbracingany por- ,tionofthe work. Approximatelyatth' imei.

f clamp orlock the thread from movement to the needle, and during the subsequent reciprtwa tions of the needle-bar and its take-up exert a strain on the thread which, in view of the tightened knots, so called, and the natural elasticity of the thread above the work, together with the leverage exerted by the loop or loops of the knotted portion on the main thread, effects the breaking of the main thr close to the knotted portion or at one of ti..- latter loops of the knotted portion.

As shown in the drawings, in its preferred form 10 indicates the bcdplate oi the machine, having the frame ll, carryingthc arm 12, which at its forward end is provided with the needle-bar guides 13 and M, in which the The needlediar is furnished with the threadguide 16, and a similar guide 17 is secured to the guide 14 or to some convenient part of this portion of the arm 12, while at the upper portion of this arm is the thread-guide 18, preferably of a yielding nature or mounted lo yield under a strain on the thread.

In the arm 12 is rotatably mounted the needle bar shaft 19, which is pivoially connected by the co11ncct-ing-r 1 d 20 with the needle-bar 15 to effect the reciprocation of the needle-bar when the shaft 19 is caused to rotate, as is usual in machines of this general nature. On this shaft 19 is secured the cam frame 12 is secured the worm needle-bar 15 is mounted to slide vertically.

21, and preferably on' that portion of thi shaft extendmg beyond the bearing m the which en gages With the gear 23, rotatebly mounted'in the bracket 24, secured to this portion of the machme and furnished with the member 25, to Which the cam 26 is removsbly secured, whereby other cams of greater or less throw or dwell may be substituted for the cam shown.

Plvotelly mounted on the arm 12 is the lever 2?, o ls end of which is positioned in the path of the cam 26, While the other endwof this lever bears against the end of the out- Wsrdly-sprmg-pressed rod 29, which Works in the bearing 30, secured in the wsllofthe arm 12 end has theinner bevel 31. l

At the upper part of the arm 12, approximately above the location of the cam 21, is secured the casing 32 having thresdguides 33 erld 34 and the opening 35. in the upper portion of this casing is preferably edjustsbly secured the clamping member 36, the lower end of which when adjusted preferably extends below the upper edge of theopemrigSS. The lower part 37 of said casirig 32 is tubular and errtends through the well or" the arm 12 end in this lower part is movably mounted the clamp ng member 38, having the rod esters slow 39 furnished with the collar 40, between which collar and the lower fixed portion 37 of the casing 32 is the expansion-spring 41, by which the rod 39 is pressed tovfard the cam 21 to move the clamping member 38 ewev from the member 36. k

The bed-piste 10 has the usual needle-hole 10, adjacent to which is movably mounted the button-clamp or Work-holder 42, of any usual construction, and preferably operated by means of the lever 43, pivotelly supported at the under side of the bed-plate and pivotslly connected With the button-clamp in the usual manner.

Journsled in bearings at the under side of the bed-piste 10 is the main shaft 44, having the worm and the gear 46. Adjacent to this main shaft is rotatably mounted the gear 47; furnished with the cam 48,- which works against the bearing 43 etthe free end of the lever 43, which end of said lever is drawn toWercl-seid cam by the usual. spring 43, and having the peripherellydisposed cam-surfaces 4-9 49, bythe sotior of ,which on said lever the button-clamp or work-holder is caused to vibrate or move. Between the grou of csrmsurfsces 4:9 49 is the dwell 50, Whic 1 is so timed with regard to the oomple tion of the group of stitches that it bears on the bearing 43" at or about the time the last stitch is completed, the result being that the Work and the needle retain their relative pnsitioiis While this dwell 50 is moriog egeinst t bearing 43", thus permitting the need d river a series of loops through the eth in the work to iooper, and these loops being srroc-essivc l -g east oil by the looper onto the next succeeding loo produces s chain which, when drawn tight, he-

sleseo comes what is called a knot 'or a. knotted finish, adapted to hold the egsmst accidental loosening,

Depending from the bed-plsteiO is the bracket 51, in which is journsled the shaft of the looper 52, this shaft having the ear 53, which is driven from the gear 54 on t a shaft 55, which is journsled in besrin s in the bracket 51v and in thebed-plste l end has the gear 56, which meshes with the. gear 57, rotstebly mounted and driven from the geer 46 on the main shsit 44.

At the under side of the berhplete '10. is formed the guide 58, (indicated in broken lines in Figs. 1 and 4,) and in this guide is movable the slide 52*, having the recess 50, in which is pivoted the finger 61, hevinq' the hook. end 62. This slide 59 is also furnished with the disgoesl slot 63, in which Works the pin 64 of the levers 65, which is pivotailly supported st the under side of the bed-plate 10 and has the pin $6, working in the groove of the cam 67', mounted on the asin shsit tel Also at the lower side of the both lets it), scent to the slide ere justelily mounteo the plates :18 and 69, csrryirig the stops 70 and 71, between which the end oithe pivoted linger 61 Works, these stops effecting the swinging of said linger on its pivot when the slide is moved heel: and forth to position the threeddoop on the looper and to prevent the distortion of said loop under stress of the moving button-clamp, whereby the loop on the loo er is so positioned that it may be cast of? on the nest succeeding loop carried downward by the needle. I

The thread Gib eerried from any ordinal thread-supply around. the guide 34, throu I 1 the opening 35 of the thread-clamping evice, behind the guide 33, mid through the guides 18, 16, and 17, or through any suitable series of guiding devices to and through the eye of the nee lie.

in the sewing operation the thread a a is carried dowi through the WOZk in the form of e loop, which loop is engsged by the hook of the looper in the usual manner, the thread being free to more to the needle through the open oi the clamping device. ()n the upward movement of the needle-bar 15 the guide 16 sets to draw the loop tight, and the cam 21 is so timed with relation to its action on the rod 3.) that as the upward movement of begins this rod is forced upward esi is clamped between the "ewe 35 end Ii'l, and hence osnnot be drawn l rom this sli ion by the taking-up action of the r -moving guide 16, thus necessarily ting the drawing action on any loose throsd which may be beneath the work.

The cars designed to be rotated at eeoh complete sewing operation included in whi l: is the formation of e group of stitches (luri against the bee-ring 4%"oi the hnllowcleznp group of stitches v mg which the carnel an-es 49 i WOIk 'actuating lever 43, the formation of the chain while the dwell is working against said bearing 43 and the drawing upward of the thread at the last upward stroke of the needle when the slack thread has been so util izr-d in forming the chain or knotted portion that there is not sufficient slack thread between the work and the thread-clamping device to permit the full upward movement of the needle without breaking the thread.

W'hen. there l ore, the can] 48 has been so rotated as to brim the dwell 50 against the bearing 43 the vibratory movement of the button-clamp ceases and the cam 2! is timed to actuate the thread-clamping member 38 through its rod 39 at approximately this point to carry the collar *0 above the level of the thin edge of the sliding rod 29. At the same time the gear 23 has been caused to rotate by the worm 22 on the needle-bar shaft to a point where the cam 26 forces outward this end of the lever 27, thus acting through said lever to move the rod 29 inward against the action of its spring and to enga e the bevel end of said rod 29 under the collar 40 of the rod 39 to hold said rod 39 in the raised position, whereby the thread is clamped, while the cam 26 is beneath the end of the lever 27.

Attention is called to the fact that the thread-elampin device is actuated by the cam 21 at each upward movement of the needle-bar; but that this clam ing device is locked in the closed position y the rod 29 during a series of stitch movements of the needle-bar only after the group of stitches is formed and during the formation of the chain which effects the knotting of the thread.

It wil thus be seen that after the locking of the thread against movement toward the needle the slack thread will be utilized in forming the locking-chain until this slack thread is not of sufficient length to follow the complete upward movement of the needlebar. A st rain will then be brought on the loops of the chain to tighten them against the sewing-stitches until a comparatively rigid tknot is t'ormed, which is illustrated in only a omparative degree in Fig. 6, the thread a (1, extending from this knotted portion around the looper and through the needle and the guides to the thread -clamp, this unused thread being adapted to yield somewhat under strain, so that when the strain of the upwardly -moving guide is brought on this yielding portion of the thread in a direction away from the rigid knot the thread will part approximately at the last link or loop ,ot' the chain, this parting being eilected bv the strain on the thread, combined with the bite formed by said last link or loop of the chain. and the leverage of one portion of said loop bent over the others.

It is of course obvious that other well known means may be used by periodically changing the lateral relation of the work and the needle, whereby the stitches are formedas, for instance, any ordinary needle-barvibratiug mechanism may be substttuted for the movable button-clamp. Nor do I wish to confine myself to this specilic form of threadclamp or to its specific form of operation. It is also evident that in some forms of machines for formin groups of stitches the loop-positioner, inc ruling the slide 59, with its related parts, might preferably be omitted, as these parts are not lncluded 1n the present invention.

Having'thus described my invention, I claim as new and desire to secure by Letters Patent- I 1. A sewing-machine comprising stitchforming means including a needle and a looper, and means for locking the thread against feeding movement during a series of loop-delivery actions of the needle.

2. A sewing-machine comprising stitchforming means including a needle and a looper, thread-elamping means through which thread is supplied to the needle, and. means for locking sald clamping means durmg a series of loop-delivery movements of the needle.

3. A sewing-machine comprising stitchforming means including a needle, a looper, means for taking up the thread, a threadclamping means through which the thread is supplied to the take-up means, and means for locking said clamping means during a series of loop-delivery movements of the needle.

4. The combination with a sewing-machine comprisin means for producing a relative movement between the needle and the work, and means for suspending such movement during the formation of a series of stitches, of means for locking the thread against feeding movement during the suspension of relative movement bctwccnthe needle and the work;

5. The combination with a sewing-machine comprising means for forming a grbup of stitches including a needle and a looper,

and means for maintaining the relative positions of the work and the needle during a series of loop-delivery movements of the needle, of means timed with relation to the completion'of the group of stitches, for locking the thread against feeding movement while the relative position of the needle and work isniaintained.

6. The combination with a sewing-machine comprising means for producing a rela tive movement between the needle and the work, and means for suspending such movement during the formation ol a series of stitches, of means for locking the thread against feeding movement whereby the con tinued loop-delivery movements of the needle will effect the drawing u. of the chainlloops toform a knot and to u timately break .mecimmem therefor, of a, needle -thre clamp, means for operating said clamp at each upward movement of 511a z ieeslle', and means for iockmg semi clamp m fife closed position during a series of movemems of the needle.

8. The combmatlon Wlth a seWmg-machine comprising 9, needle-her, al driveshafi;

therefor, a threxxd-emmp having a movable member adapted t0 be actuated b the r0tetion of said shaft, and means controlled by the rotation of said shaft for iocking the =movablemember of the thread-clamp m the closed posjtien during e series of-sretations of the needlekbar shaft as described. V

In testimony whereof I effix my signature in presence of two Witnesses.

V ROBERT L. LYONSU Witnessez S. GOOSTRAY,

H. J. MILLER 

